ABSTRACT
Objective To report the distribution and antibiotic resistance of bacterial strains isolated in the First Affiliated Hospital of Anhui Medical University during 2016 for improving clinical treatment of bacterial infections. Methods Antimicrobial susceptibility testing was carried out according to a unified protocol using Kirby-Bauer method or automated systems. The results were interpreted according to the clinical and laboratory standards institute (CLSI) 2015 breakpoints, and analyzed using WHONWT 5.6. Results A total of 5 406 clinical isolates were collected during 2016, of which gram positive organisms accounted for 25.6％ (1 386/5 406) and gram negative organisms 74.4％ (4 020/5 406). The strains were mainly isolated from respiratory tract (35.4％, 1 913/5 406) and urine (26.7％, 1 441/5 406). The most frequently isolated microorganisms were E. coli (23.1％, 1 247/5 406), followed by K. pneumoniae (12.1％,654/5 406). The prevalence of MRSA was 52.2％ (166/318). The prevalence of MRCNS was 80.3％ (462/575). Of the ESBLs producers, E. coli accounted for 59.7％ (745/1 247), and K. pneumoniae accounted for 30.6％(200/654). ESBLs-producing strains showed significantly higher resistance rates to most antibiotics than non-ESBLs-producing strains. All the E. faecalis strains were susceptible to vancomycin. A few (0.2％) of the E. faecium strains were resistant to vancomycin, which were all from urine specimens. A total of 1 046 (19.3％, 1 046/5 406) carbapenemresistant strains were isolated. Most Enterobacteriaceae isolates were still highly sensitive to carbapenems. Carbapenem-resistant isolates were mainly A. baumannii (41.1％, 430/1 046), P. aeruginosa (17.4％, 182/1 046)) and K. pneumoniae (12.0％, 126/1 046). Most Acinetobacter strains were resistant to most of the antibiotics tested. Conclusions Antimicrobial resistance is increasing in the clinical isolates in this hospital. We should continue to strengthen antimicrobial stewardship, prescribe antibiotics for strict indications, and improve rational antibiotic use.
ABSTRACT
Objective To investigate the clinical distribution and drug resistance of multidrug-resistant (MDR)Pseudomonas aeruginosa to provide reference for clinical rational use of antibacterial drugs.Methods The strains were originated from bacterial culture in the samples of sputum,urine and wound secretion collected from the inpatients admitted in our hospital from January 2009 to December 2013.Results 200 strains of Pseudomonas aeruginosa were isolated during this period,in which 51 strains were MDR,accounting for 25.5%.The isolated MDR Pseudomonas aeruginosa strains were mainly distributed in the the respiratory de-partment(80.4%)and the surgical department(17.9%).MDR strains isolated from the sputum specimens accounted for 64.7%, followed by the wound secretion(19.6%)and urine(11.8%).Pseudomonas aeruginosa was seriously resistant to ampicillin-sulbac-tam with the resistance rate of was 100.0%,but had the low resistance rate to amikacin,imipenem,meropenem,piperacillin/tazobactam,ciprofloxacin,levofloxacin,polymyxin E,which were 28.9%,29.4%,25.0%,30.4%,34.5%,34.5% and 8.3%;the resistance rate to commonly used antibacterial drugs was 39.0%-58.3%.14 strains were pan-drug resistant Pseudomonas aerugi-nosa(PDR-PA);The detection rate was 7.0%.Conclusion The drug resistance of MDR Pseudomonas aeruginosa is more serious, the clinical application of anibiotics should be perfromed based on the result of drug susceptibility test.
ABSTRACT
Objective To investigate the correlation between acquired drug resistance-related genes and mobile genetic elements from pandrug-resistant Acinetobacter baumannii. Methods Fifty-three horizontal transfer drug resistance-related genes ( β-lactamases,aminoglycoside and quinolones resistance related) and 12 mobile genetic elements (including zygosity plasmid,transposon,insertion sequence and integron) were detected by polymerase chain reaction (PCR) in 20 clinical isolates of pandrug-resistant Acinetobacter baumannii.Index cluster analysis was performed to explore the correlation.Results In 20 strains of pandrug-resistant Acinetobacter baumannii,there were 3 types of β-lactamases related genes (TEM-1,ADC-30,OXA-23 ),4 types of aminoglycoside modifying enzyme genes [ aac (3)-Ⅰ,aac(6′)-Ⅰ b,ant( 3″)-Ⅰ and aph( 3′)-Ⅰ ],and 5 kinds of mobile genetic elements ( int Ⅰ 1,tnpU,tnp513,IS26 and ISAba1 ). Index cluster analysis showed high correlations between resistance genes [TEM-1,ADC-30,aac( 6′)-Ⅰ b,ant( 3″)-Ⅰ,abeB,qacE Δ1] and mobile genetic elements ( int Ⅰ 1,tnpU,tnp513,IS26,ISAba1 ).Conclusion Clinical isolated pandrug-resistant Acinetobacter baumannii carries several acquired drug resistance-related genes and mobile genetic elements,and there may be a close association between them.